Polycarbonates prepared by the melt reaction of dihydroxy compounds with an ester-substituted diaryl carbonate produce salicylate compounds as a by-product. For example, where polycarbonate is produced by the melt reaction of bisphenol A and bis-methyl salicyl carbonate this by-product is methyl salicylate. The reaction is fast enough to proceed in a reactive extruder. While the reaction progresses in the extruder the methyl salicylate by-product is removed through vent ports along the length of the extruder. Further, it is desirable to have only minimal amounts of the salicylate by-product in the resulting polycarbonate. It is also desirable to maximize the throughput of the extruder. However, the higher rate of throughput of the extruder results in a higher amount of the salicylate by-product produced. It would be extremely beneficial to produce polycarbonate on an extruder with a high throughput while minimizing the by-product salicylate contained in the product.